| "Implementation of tzinfo classes for use with datetime.datetime." |
| |
| import time |
| from datetime import timedelta, tzinfo |
| from django.utils.encoding import smart_unicode, smart_str, DEFAULT_LOCALE_ENCODING |
| |
| class FixedOffset(tzinfo): |
| "Fixed offset in minutes east from UTC." |
| def __init__(self, offset): |
| if isinstance(offset, timedelta): |
| self.__offset = offset |
| offset = self.__offset.seconds // 60 |
| else: |
| self.__offset = timedelta(minutes=offset) |
| |
| sign = offset < 0 and '-' or '+' |
| self.__name = u"%s%02d%02d" % (sign, abs(offset) / 60., abs(offset) % 60) |
| |
| def __repr__(self): |
| return self.__name |
| |
| def utcoffset(self, dt): |
| return self.__offset |
| |
| def tzname(self, dt): |
| return self.__name |
| |
| def dst(self, dt): |
| return timedelta(0) |
| |
| class LocalTimezone(tzinfo): |
| "Proxy timezone information from time module." |
| def __init__(self, dt): |
| tzinfo.__init__(self) |
| self._tzname = self.tzname(dt) |
| |
| def __repr__(self): |
| return smart_str(self._tzname) |
| |
| def utcoffset(self, dt): |
| if self._isdst(dt): |
| return timedelta(seconds=-time.altzone) |
| else: |
| return timedelta(seconds=-time.timezone) |
| |
| def dst(self, dt): |
| if self._isdst(dt): |
| return timedelta(seconds=-time.altzone) - timedelta(seconds=-time.timezone) |
| else: |
| return timedelta(0) |
| |
| def tzname(self, dt): |
| try: |
| return smart_unicode(time.tzname[self._isdst(dt)], |
| DEFAULT_LOCALE_ENCODING) |
| except UnicodeDecodeError: |
| return None |
| |
| def _isdst(self, dt): |
| tt = (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second, dt.weekday(), 0, -1) |
| try: |
| stamp = time.mktime(tt) |
| except (OverflowError, ValueError): |
| # 32 bit systems can't handle dates after Jan 2038, and certain |
| # systems can't handle dates before ~1901-12-01: |
| # |
| # >>> time.mktime((1900, 1, 13, 0, 0, 0, 0, 0, 0)) |
| # OverflowError: mktime argument out of range |
| # >>> time.mktime((1850, 1, 13, 0, 0, 0, 0, 0, 0)) |
| # ValueError: year out of range |
| # |
| # In this case, we fake the date, because we only care about the |
| # DST flag. |
| tt = (2037,) + tt[1:] |
| stamp = time.mktime(tt) |
| tt = time.localtime(stamp) |
| return tt.tm_isdst > 0 |